Solar tracking systems are employed in photovoltaic and solar thermal applications to increase the collection of sunlight by aiming the photovoltaic panels or collectors at the sun throughout sun's daily movement in the sky. In doing so, tracking systems incorporate pivot points or bearings on which to rotate. These bearings may be placed at the center of gravity of the tracking system or may be located underneath the photovoltaic or collector array.
The array balancing approach, the technique of placing the bearing housings at or near the center of gravity of the array, has the benefit of alleviating the stress on the positioning drive apparatus because there is little or no overhung weight to create an inherent moment load on the positioning system. Furthermore, balancing the mechanical system about the center of gravity also reduces or eliminates the torsion deflection of the supporting structure, which may allow for less structure material requirements.
To counterbalance with a pivot point positioned at or near the center of gravity of a tracking system, most designs must locate the pivot points above the surface of the photovoltaic modules or thermal collectors. This creates complexity in the structure, in the bearing pivot points, and creates density inefficiencies because there must be spaces in the collection surface where the bearings are located. The spaces where the center of gravity bearings are located are commonly referred to as dead space in the system because solar collection is not possible at these areas of the system. When used in a large photovoltaic solar farm or thermal collector, these dead spaces in the North/South length of the tracker row get multiplied by the East/West spacing that is required between the trackers and result in considerable density reduction across an entire field.
Accordingly, there is a need for an improved system for balancing the rotation of a tracking system. There also is a need for an improved balancing system that eliminates dead spaces in the system. There is a need for an improved balancing system that is less complex, requires less structural material, and results in lower torsional deflection in the system.